Bovine babesiosis: a review of recent advances

RESUMO

Bovine babesiosis, caused by parasites of the genus babesia, is one of the world's most severe tick-borne problems of cattle in temperate to tropical areas. In the America Babesia bovis and B bigemina are the causative agents, with the former considered to produce the greatest economic impact. The great complexity of the relationship causal agent-vector-host has severely hindered the efforts towards the production of a safe, long-lasting, solid-protection inducing vaccine. Recent importan contributions that have encourage the study of these agents include the development of in vitro cultivation systems, procedures for the isolation of single infected-erythrocytes, density gradient-based centrifugation systems for the isolation and concentration of both infected erythrocytes and merozoites, isozyme detection and differentitation systems that help discrimate between parasite species, and development of DNA-based diagnostics and characterization protocols. Currently, the study of the cellular immune response against these parasites is taking new endeavors in order to discern the relationship between B cells, T cell, macrophages and their product and parasites leading to the establishment of solid, long-lasting protection. In an attempt to design a rational vaccine, T cell lines and clones are being established, and phagocytosis of infected erythrocytes and their antigens studied to try to pinpoint relevant epitopes